资源描述：
《实用医学英语翻译第三单元》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、TheMuscularSystemMuscleisthetough,elastictissuethatmakesbodypartsmove.Allanimalsexceptthesimplestkindshavesometypeofmuscle.Peopleusemuscletomakevariousmovements,suchaswalking,jumping,orthrowing.Musclesalsohelpinperformingactivitiesnecessaryforgrowthandformaintainingastrong,healthybo
2、dy.Forexample,peopleusemusclesinthejawtochewfood.Othermuscleshelpmovefoodthroughthestomachandintestines,andaidindigestion.Musclesintheheartandbloodvesselsforcethebloodtocirculate.Musclesinthechestmakebreathingpossible.肌肉系统肌肉是一种结实而有弹性的组织，能够使身体活动。除了最简单的几种动物，所有动物都有某些类型的肌肉。人们用肌肉来完成各种运动，
3、如行走、跳跃或者投掷。肌肉也有助于执行身体生长和保持强壮、健康的身体所必需的各种活动。例如，人们用位于下巴的肌肉咀嚼食物。其他肌肉帮助食物通过胃和肠道，帮助消化。心脏和血管处的肌肉促使血液循环。胸部肌肉使人能呼吸。TypesofMusclesThehumanbodyhasmorethan600majormuscles.About240ofthemhavespecificnames.Ingeneral,musclesareclassifiedintothreegroups:(1)skeletalmuscles,(2)smoothmuscles,and(3)car
4、diacmusclesSkeletalmuscleshelpholdthebonesoftheskeletontogetherandgivethebodyshape.Theyalsomakethebodymove.Skeletalmusclesmakeupalargepartofthelegs,arms,abdomen,chest,neck,andface.Thesemusclesvarygreatlyinsize,dependingonthetypeofjobtheydo.Forexample,eyemusclesaresmallandfairlyweak,
5、butthemusclesofthethigharelargeandstrong.肌肉的类型人体有超过600个主要的肌肉。约240块有特定的名字。一般来说，肌肉分为三组:(1)骨骼肌,(2)平滑肌,和(3)心肌。骨骼肌帮助把骨与骨连接在一起，形成人体态。他们还能使身体活动。我们腿上的大部分肌肉、以及手臂、腹部、胸部、脖子和脸是由骨骼肌组成。根据他们各自的作用，这些肌肉大小不一。例如，眼部肌肉小而弱，大腿肌肉却大而壮。Whenapersonstandserect,manyskeletalmusclescontracttomakethebodyrigid.Skel
6、etalmusclesalsocanmakeonepartofthebodymovewhileanotherpartstaysstiff.Skeletalmusclesactbothwaysbecausetheyworkinpairs.Onemuscleofeachpairiscalledtheflexor.Itbendsajointandbringsalimbclosertothebody.Theothermuscle,theextensor,doestheopposite.Forexample,thebicepsmuscleinthefrontoftheu
7、pperarmisaflexor.Whenthismusclecontracts,theelbowbendsandtheforearmandhandmovetowardtheshoulder.Thetricepsmuscleinthebackoftheupperarmisanextensor.Whenitcontracts,theelbowstraightensandtheforearmandhandmoveawayfromtheshoulder.Atthesametime,thebicepsrelaxessothetricepscanpullitbackto
8、itsoriginallength.当
